Leave it to American business to twist a 5,000-year-old Hindu philosophy of gentle poses into an emotional knot.

In a matter of weeks, a steamy sex scandal has prompted the resignation of a yoga world superstar, roiled the discipline’s trendiest branch, sparked a mass exodus of teachers and transformed part of the $5.7 billion industry from “namaste” to nasty.

The tumult – rooted in the popular form called Anusara – isn’t entirely surprising, according to some yoga disciples, although it’s undeniably ironic given the ancient regimen’s tenets of tranquility and self-restraint.

“If you can put your feet behind your head, it doesn’t mean you’re enlightened or that you’re not going to make mistakes,” said Annie Prasad Freedom, owner of the Samadhi Center for Yoga & Meditation in Denver. The studio offers classes in Anusara and other types of yoga.

The eye of this yoga storm swirls around John Friend, a charismatic entrepreneur who earned a finance degree then went into the yoga field – a juxtaposition of the usual path: a yogi who goes into business. Friend founded Anusara yoga in 1997 – and ultimately Anusara Inc. – draping his version on a “life-affirming” Tantric ideology “of intrinsic goodness,” selling a “celebration of the heart that looks for the good in all people and all things,” according to his former company’s website. As the primary investor in Anusara, Friend prospered while his venture boomed and he charmed yoga conference audiences around the nation. In 15 years, his enterprise licensed 1,000 Anusara teachers and gained more than a half million followers in 70 countries.

Then the tight-knit Anusara family unraveled. Last month YogaDork.com republished anonymous accusations that Friend had engaged in sexual affairs with several married Anusara employees and teachers. On Feb. 16, Friend resigned as CEO of Anusara Inc. saying the company would become a non-profit run by one of his Anusara teachers.

Now, as dozens of licensed Anusara teachers rush to distance themselves from Friend and rebrand their businesses (calling themselves the “Yoga Coalition,”) the scandal has shed fresh light on the fads that so often drive business in the yoga world. Interviews with yoga industry experts – including studio owners, teachers and trade journalists - found some concerned that the fiasco could taint the industry although turn away casual consumers.

None reported any financial impact so far, but the jury is out on whether Anusara – once a cornerstone of modern yoga – can survive its founder’s fall and the mass flight of many star teachers. Still, some pointed out that Bikram yoga, which features studios heated to over 100 degrees, weathered a smaller sex-related controversy just a year ago.

With some 600,000 students following Anusara, according to published estimates, the relatively young branch comprises about 4 percent of a U.S. yoga market that numbers 15.8 million practitioners who spend nearly $6 billion a year on classes, vacations, clothing, books, DVDs and magazines. How did Anusara gain such a quick, passionate foothold?

“Simply put, John put a smiley face on Iyengar yoga, said yoga expert Leslie Kaminoff, referring to a form known for its use of props, including belts, blankets and blocks to help people perform postures.

"People flocked to him,” said Kaminoff, author of “Yoga Anatomy” and executive director of The Breathing Project, a New York yoga studio and school. “Many practitioners and teachers loved the anatomical precision of Iyengar yoga, but were tired of getting slapped, bullied and yelled at in class. (Friend) found something to sell to the yoga community that they really wanted, and his timing was good.”

At the same time, word about the upstart branch spread rapidly after respected, well-known yoga teachers espoused it on their blogs, said Mary Alice Mitchell, director of media and partner relations for YogaVibes.com, an online, subscription-based yoga class provider.

While Mitchell says some Anusara teachers will be “adversely impacted” because it will be difficult to continue using the brand name, she doesn't see any collateral damage to the larger yoga universe.

“It's sensational, but not new,” Mitchell added. “There have been other ‘guru sex scandals’ in the recent past. The overwhelming cohort of people who practice yoga come to it in search of one or more of its mind/body benefits, not to practice a specific style or follow a certain leader.”

In February 2011, Details magazine profiled Bikram Choudhury, founder of Bikram yoga. The piece, titled “The Overheated, Oversexed Cult of Bikram Choudhury,” described the guru’s X-rated language to some students during one class and reported “the stories about him having sex with students. When (the magazine questions) him about this, he doesn’t deny it – he claims (students) blackmail him.”

“Since Bikram's well-documented legal, financial and sexual antics haven't sunk him yet,” says yoga author Kaminoff, “ I don't think John's diddlings will have much impact” on the rest of the industry.

Which begs the question: How do the different yoga branches battle to lure customers while retaining some focus on spirituality?

“Yoga styles don't generally advertise that they're better than others, but they do compete for students, and for enrollment in teacher training programs, which are the big money-makers for most studios," Kaminoff said.

The industry is closely tracked by Yoga Journal, which is doing a new study as a follow-up to its 2008 report than found Americans dole out $5.7 billion annually on yoga sessions and products. That marked an 87 percent increase over U.S. yoga spending in 2004.

“What we’re going to find now? I don’t have the data yet, but my guess is the number of dollars spent now is pretty healthy – and has maybe gone up,” said Dayna Macy, the magazine’s communications director. She bases part of that prediction on the conferences hosted by Yoga Journal: the number of their events has increased to five per year, attracting 1,500 to 2,000 people each “and they all sell out.”

At YogaVibes.com, which offers Anusara classes via its website, “we have not seen any negative impact on our sales or traffic since this story broke,” Mitchell said.

In Miami, Green Monkey opened its first studio three years ago and today the business operates two more studios in that city. At all three locations, business has been rising both in terms of student numbers and revenue, said company co-president Michael Block.

Despite the Anusara mess, Green Monkey will actually be adding three more Anusara-inspired classes this month at its South Miami studio to supplement the current Anusara-inspired class now offered at its Miami Beach studio, said Jessie Lurie, power yoga instructor at Green Monkey.

Still, larger worries loom of an Anusara-inspired taint among more casual yoga students across the country, added Yoga Journal’s Macy.

“The one thing (the Anusara scandal) might affect, sadly so, is public perception of all yoga,” Macy said. “What the casual consumer takes away from that is … don’t do yoga, you’re going to be attacked by a sex-crazed teacher. I think that’s absurd. … If you believe that a teacher is behaving in a way that is inappropriate, for heaven sakes use your brains and don’t follow what the teacher is saying.”

“But I think that unquestionably yoga (in general) can and will ride through this,” she added. “This has been around 5,000 years. One man is not going to single-handedly tear down the fabric of yoga. He is not that powerful.”